Group addressed frame delivery over multi-link systems

ABSTRACT

Embodiments may relate to group addressed frame delivery over multi-link systems. Systems and methods are configured for identifying, by an access point (AP) multilink device (MLD) in a wireless network, a first sequence number space (SNS) that is to be used by the AP MLD to transmit data to a non-AP MLD over a first communications link and a second communications link, wherein frames with identical data that are transmitted over the first and second communications links will have an identical first SN based on the first SNS; identifying, by the MLD in the wireless network, the first SN based on the first SNS; and transmitting, by the AP MLD in the wireless network, a frame that includes the data to the non-AP MLD based on the first SN.

CLAIM OF PRIORITY

This application claims priority under 35 U.S.C. § 119(e) to U.S. PatentApplication Ser. No. 63/122,389, filed on Dec. 7, 2020, the entirecontents of which are hereby incorporated by reference.

BACKGROUND

In Wi-Fi systems, group cast frames (BFCs) are transmitted independentlyover multiple links of a multi-link device (MLD), with each link usingits own sequence number (SN) space. As a result, a non-access point (AP)MLD may receive undetectable duplicated group addressed frames (GAFs)when it switches from one link to another. Additionally, other frametypes that share the same sequence number space (SNS) type 1 (SNS1) withgroup cast frames (GCFs) also have duplicate issues over MLD.

SUMMARY

This specification describes processes for group addressed framedelivery over multi-link systems. Embodiments herein relate to a numberof designs that may increase the efficiency of MLD and, moreparticularly, GCR operation in MLD. For example, for transmission overMLD, new SNS design(s) may allow proper duplicate detection of one orboth of false negatives and false positives. Additionally, theabove-described GTK and PN architecture for MLD may allow unifiedunicast-BA and group cast BA operation. Additionally, embodiments mayrelate to a method for GCR-BA operation over MLD. For example,embodiments relate to defining the GCR-BA over MLD procedure where theGCR-BA agreement is established at the MLD level. Additionally,embodiments relate to a GCR BlockAckReq variant, which may allow aTID-specific BA request. Other embodiments may relate to a method fortransmitting additional copies of GCFs using MLD_address as the TA.Other embodiments may be described herein.

The processes described herein enable one or more of the followingadvantages. For 11be_D0.1, group cast frames (GCFs) are transmittedindependently over multiple links of MLD, with each link using its ownSN space (such as SNS1_link_i). As a result, a non-AP MLD can receiveundetectable duplicated GAFs when it switches from one link to another.The processes and systems described herein enable detection ofduplicated GAFs. Additionally, other frame types that share the sameSNS1 with GCFs also have duplicate issues over MLD. The systems andmethods described herein account for GCR operation over MLD. GCR BlockAck is one type of GCR operation. For 11be_D0.1, a unicast block-ackoperation is specified over MLD. The systems and methods describedherein unify block-ack operation for unicast BA and group cast BA.

The one or more advantages described herein are enabled by one or moreof the implementations described herein, such as in the examples sectionsubsequently described.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A depicts an example wireless communication network, in accordancewith various embodiments.

FIG. 1B depicts an example of an AP MLD and a non-AP MLD communicativelycoupled with one another by a plurality of links.

FIG. 2 depicts an example wireless computing device, in accordance withvarious embodiments.

FIG. 3 depicts an example of SNS1 conflicts in a wireless network, inaccordance with various embodiments.

FIG. 4 depicts an example of use of a shared SNS, in accordance withvarious embodiments.

FIG. 5 depicts an alternative example of use of a shared SNS, inaccordance with various embodiments.

FIG. 6 depicts an example of a procedure related to group cast retries(GCR) block acknowledgment (BA) (collectively, GCR-BA) over multiplelinks, in accordance with various embodiments.

FIG. 7 depicts an alternative example of a procedure related to GCR-BAover multiple links, in accordance with various embodiments.

FIG. 8 depicts an example of group temporal key (GTK) and packet number(PN) design for use with multiple links, in accordance with variousembodiments.

FIG. 9 depicts an example of group frame reception on multiple links, inaccordance with various embodiments.

FIG. 10 depicts an example of frame processing by a Group Frames Reorderbuffer, in accordance with various embodiments.

FIG. 11 depicts an example of an additional copy GCF transmitted basedon MLD medium access control (MAC) addresses (MLD_addresses), inaccordance with various embodiments.

FIG. 12 depicts a flow diagram showing an example process for groupaddressed frame delivery over multi-link systems.

FIG. 13 depicts a flow diagram showing an example process for groupaddressed frame delivery over multi-link systems.

FIG. 14 depicts a flow diagram showing an example process for groupaddressed frame delivery over multi-link systems.

FIG. 15 depicts a flow diagram showing an example process for groupaddressed frame delivery over multi-link systems.

FIG. 16 depicts a flow diagram showing an example process for groupaddressed frame delivery over multi-link systems.

DETAILED DESCRIPTION

FIG. 1A illustrates an example of a wireless communication network 100.In this example, the network 100 includes APs 110 a and 110 b configuredto wirelessly communicate with one or more stations (STAs) 120 a-120 i(referred to collectively as “STAs 120”). For example, AP 110 a is shownin wireless communication with STAs 120 a-120 e, and AP 110 b is shownin wireless communication with STAs 120 f-120 i. Each of the APs 110 aand 110 b (referred to collectively as “APs 110”) are coupled to anetwork 135, such as the Internet or another interconnected network ofcomputerized devices, thereby providing the STAs 120 with access to thenetwork 135. Note that the wireless communication network 100 caninclude additional or fewer APs or STAs without departing from the scopeof the present disclosure.

In some embodiments, certain of the STAs (e.g., STA 120 f) may becoupled with an AP (e.g., AP 110 b) by more than one communication link(e.g., communication links 130 a and 130 b). In this case, STA 120 f maybe referred to as a non-AP MLD. Similarly, AP 110 b may be referred toas an AP MLD. In some embodiments, the communications links maycommunicate in different frequency bands. For example, communicationlink 130 a may provide communication on a 2.4 gigahertz (GHz) frequencyband, while communication link 130 b may provide communication on a 5GHz frequency band. It will be understood that, in other embodiments,the frequency band may have a range, or may have different values.Similarly, communication between an AP MLD and a non-AP MLD may occur ora larger number of communication links than are shown in FIG. 1A.

FIG. 1B depicts a more detailed example of an AP MLD coupled with anon-AP MLD by a plurality of communication links. Generally, the AP MLDmay have its own media access control address. Similarly, the non-AP MLDmay have its own MAC address. The APs and STAs may be communicated by aplurality of communication links as depicted in FIG. 1 b . Furtherdetails of the AP MLD and non-AP MLD are described below with respect toFIG. 11 .

Returning to FIG. 1A, each of the APs 110 and STAs 120 can be acomputing device, such as the wireless computing device 200 of FIG. 2 .For example, one or more of the APs 110 or STAs 120, or both, can be, orcan be a subsystem of, a substantially portable wireless computingdevice, such as a smart phone, a hand-held device, a wearable device(e.g., a smart watch), a tablet, a laptop, or a motor vehicle, amongother portable wireless devices. As another example, one or more of theAPs 110 or STAs 120, or both, can be a substantially stationarycomputing device, such as a set top box, a router, a media player (e.g.,an audio or audiovisual device), a gaming console, a desktop computer,an appliance, or a base station, among other stationary devices.

In an example, each of the APs 110 include baseband processing circuitryand one or more radio transceivers. For example, in a MLD such as AP 110b, there may be a separate radio transceiver for each of communicationlinks 130 a and 130 b The baseband processing circuitry can be realizedby, for example, one or more processors (or processor cores) configuredto execute stored program instructions as described herein. In anexample, the radio transceiver is configured to: receive basebanddownlink signal(s) from the baseband processing circuitry, convert thebaseband downlink signal(s) into radio-frequency (RF) downlinksignal(s), and transmit the RF downlink signal(s) onto a wireless mediumusing one or more antennas. The radio transceiver is further configuredto: receive RF uplink signal(s) from the wireless medium using the oneor more antennas, convert the RF uplink signal(s) to baseband uplinksignal(s), and provide the baseband uplink signal(s) to the basebandprocessing circuitry. The radio transceiver can include one or moretransmit chains (e.g., one transmit channel per antenna) and one or morereceive chains (e.g., one receive chain per antenna).

Similar to the APs 110, each of the STAs 120 can include basebandprocessing circuitry and one or more radio transceivers. For example,similarly to AP 110 b, if a STA is a non-AP MLD such as STA 120 f, thenthe STA 120 f may include a separate radio transceiver for each ofcommunication links 130 a and 130 b. The baseband processing circuitrycan be realized by one or more processors (or processor cores)configured to execute stored program instructions as described herein.In an example, the radio transceiver is configured to: receive basebanduplink signal(s) from the baseband processing circuitry, convert thebaseband uplink signal(s) to RF uplink signal(s), and transmit the RFuplink signal(s) onto a wireless medium using one or more antennas. Theradio transceiver is further configured to: receive RF downlinksignal(s) from the wireless medium using the one or more antennas,convert the RF downlink signal(s) to baseband downlink signal(s), andprovide the baseband downlink signal(s) to the baseband processingcircuitry. The radio transceiver can include one or more transmit chains(e.g., one transmit channel per antenna) and one or more receive chains(e.g., one receive chain per antenna).

The APs 110 device and STAs 120 device can communicate using one or morewireless communication techniques. In an example, the APs 110 device andSTAs 120 device communicate using wireless local area networking (WLAN)communication technology (e.g., IEEE 802.11/Wi-Fi based communication)or other techniques based on WLAN wireless communication. In someexamples, the APs 110 device and STAs 120 device may further communicateusing one or more other wireless communication protocols, such asBluetooth (BT), Bluetooth Low Energy (BLE), near field communication(NFC), GSM, UMTS (WCDMA, TDSCDMA), LTE, LTE-Advanced (LTE-A), 5G NR,3GPP2 CDMA2000 (e.g., 1×RTT, 1×EV-DO, HRPD, eHRPD), or combinations ofthem, among other wireless communication protocols.

In an example, each of the APs 110 are configured to perform downlinkspatial multiplexing to one or more of the coupled STAs 120. Downlinkspatial multiplexing refers to the ability to transmit two or morespatial streams to a STA 120, where the two or more spatial streams aresuperposed on the same set of time-frequency resources.

FIG. 2 illustrates an example wireless computing device 200 configuredfor use in conjunction with various aspects of the present disclosure.In this example, the device 200 includes a memory 202, a processor 204,wireless communication circuitry 206, and one or more antennas 208. Theprocessor 204 is configured to execute instructions and manipulate datato perform operations of the device 200, including operations usingalgorithms, methods, functions, processes, flows, and procedures asdescribed herein. The processor 204 can be, for example, a centralprocessing unit (CPU), a reduced instruction set computing (RISC)processor, a complex instruction set computing (CISC) processor, agraphics processing unit (GPU), a digital signal processor (DSP) such asa baseband processor, a field-programmable gate array (FPGA), anapplication-specific integrated circuit (ASIC), a radio-frequencyintegrated circuit (RFIC), or combinations of them, among otherprocessors. Although illustrated as a single processor 204 in FIG. 2 ,two or more processors 204 can be used in some implementations.

The processing element 204 can include or be coupled to one or morelocal and/or system memory elements, such as the memory 202. The memory202 can include any of a variety of permanent/non-permanent andvolatile/non-volatile memory and media devices, and can storeinstructions and/or data as described herein. For example, memory 202could be RAM serving as a system memory for processing element 204.Other types of memory and functions are also possible. Althoughillustrated as a single memory 202 in FIG. 2 , two or more memories 202(of the same or different types) can be used in some implementations ofthe device 200.

The device 200 also includes wireless communication circuitry 206. In anexample, the wireless communication circuitry 206 (sometimes referred tohere as a “radio”) includes analog and/or digital circuitry components.In general, a radio can include any combination of a baseband processor,analog RF signal processing circuitry (e.g., filters, mixers,oscillators, amplifiers, etc.), and digital processing circuitry (e.g.,for digital modulation as well as other digital processing). Similarly,the radio can implement one or more receive and transmit chains usingthe aforementioned hardware. For example, the wireless device 200 canshare one or more parts of a receive chain and/or a transmit chainbetween one or more wireless communication technologies, such as thosediscussed above. The wireless communication circuitry can include or becoupled to one or more antennas 208.

Note that the wireless communication circuitry 206 can include adiscrete processor or processing element in addition to the processor204. For example, the processor 204 can be an ‘application processor,’while wireless communication circuitry 206 can include its own ‘basebandprocessor.’ Alternatively (or in addition), the processor 204 canprovide processing capability for the wireless communication circuitry206. The device 200 can communicate using any of various wirelesscommunication technologies by way of wireless communication circuitry206 and the antenna(s) 208.

As noted above, in embodiments where the device 200 is, implements, oris implemented by an AP MLD or a non-AP MLD such as those shown in FIG.1A or 1B, the device 200 may include a plurality of wirelesscommunication circuitry 206. For example, the device 200 may include afirst wireless communication circuitry 206 for a first link (e.g.,communication link 130 a) and a second wireless communication circuitry206 for a second link (e.g., communication link 130 b).

The device 200 can also include any of a variety of other components(not shown) for implementing device functionality, depending on theintended functionality of the device 200, which can include furtherprocessing and/or memory elements, one or more power supply elements(which may rely on battery power and/or an external power source), userinterface elements (e.g., display, speaker, microphone, camera,keyboard, mouse, touchscreen, etc.), additional communication elements(e.g., antenna(s) for wireless communication, I/O ports for wiredcommunication, communication circuitry/controllers, etc.) and/or any ofvarious other components.

The components of the device 200, such as the memory 202, processor 204,wireless communication circuitry 206, and antenna(s) 208, can beoperatively coupled using one or more intra-chip or inter-chipinterconnection interfaces. As an example, a USB high-speed inter-chip(HSIC) interface can be provided for inter-chip communications betweenthe processor 204 and the wireless communication circuitry 206.Alternatively (or in addition), a universal asynchronous receivertransmitter (UART) interface, a serial peripheral interface (SPI),inter-integrated circuit (I2C), system management bus (SMBus), and/orany of a variety of other communication interfaces can be used forcommunications between the memory 202, processor 204, wirelesscommunication circuitry 206, and/or any of various other devicecomponents. Other types of interfaces (e.g., peripheral interfaces forcommunication with peripheral components within or external to device200, etc.) can also be provided as part of device 200.

The transmitter and receiver use sequence numbers in transmitted framesto identify each transmitted and received frame for duplicate detection.Over the time WLAN has become more complex communication system,multiple sequence number spaces (SNSes) are used for duplicate detectionof different frame types, QoS levels as well as receivers andtransmitters. One of such sequence number space is SNS1.

SNS1 was the first sequence number space that was introduced to WLAN. Inthe early days all frames, unicast and group addressed as well as dataand management frames were transmitted using the SN (sequence number)from the same SNS1. Also, APs used the same SNS1 for all STAs, i.e., theSNS1 was only transmitter specific and AP did not have receiver specificSN in use. The SN in the transmitted consecutive group or individuallyaddressed frames may be increased by a value larger than 1. Such a broaduse of a single SNS1 caused challenges to the SNS1 handling for framedelivery over multiple links.

Over the time, more SN spaces have been introduced. QoS framework addeda separate SNS, called SNS2, for unicast frames per receiver and QoSpriority level (TID), that is, SNS2 is indexed by <address 1 (i.e.,receiver address), TID>. The introduction of multiple SNSs were neededto allow efficient block-ack use, i.e. SN may be increased by one forthe consecutively transmitted frame, and the block-ack bit map, and thescoreboard that keeps record of the received frames could use each bitefficiently.

The SN use for the group addressed frame transmission has so far notbeen evolving similarly as for unicast frames transmission. This hascaused duplicate detection problem for the group addressed framedelivery over a new multi-link devices (MLDs). Embodiments herein relateto techniques or structures that resolve one or more of theabove-described problems.

FIG. 1B shows architecture 150, where new multi-link devices (MLDs) maycommunicate over multiple links 156, 158, 160. For instance, one AP MLD152 may have multiple affiliated APs 162, 164, 166. The legacy STAs 168,170, 172, as used herein, refer the single-link STAs that are capable toonly associate with a single AP and see the AP MLD 152 as a collectionof multiple APs 162, 164, 166. A legacy STA 168 can associate with onlya single AP 162 and receive all unicast and group addressed frames fromthis associated AP 162. The non-AP MLD devices 154 can create MLD setupthat allows the non-AP MLD devices 154 to receive unicast and groupframes from any AP 162, 164, 166 which is part of the ML setup.

As used herein, a non-AP MLD 154 may be a device such as STA 120 f ofFIG. 1A that is coupled with a single AP (e.g., AP 110 b) by a pluralityof communication links (e.g., links 130 c and 130 e). In addition, itmay be desirable to perform GCR (Groupcast with Retries) operation in anetwork that includes MLDs. One example of such GCR operation is GCR-BA(Block Ack). Generally, it may be desirable to unify BA operation forunicast-BA and GCR-BA for MLD. Embodiments herein relate to techniquesor structures that resolve one or more of the above-described problems.

In legacy networks, an AP and STA may communicate using multicast(transmission of a string of packets from an AP to a group of STAs) orunicast (transmission of a string of packets between a single AP and asingle STA). As used herein, a “legacy network” refers to a network thatincludes only single-link STAs (e.g., STAs that are coupled with an APby only a single link). By contrast, embodiments herein relate tonetwork that include both single-link STAs and MLDs. The communicationperforms duplicated detection using SNs, which are assigned to frames ofthe transmission. Each communication link may be assigned its own SNS.Additionally, each packet in the communication may be assigned a PN. ThePNs may be included in an encrypted portion of the packet to prevent areplay attack (e.g., an attack in which a packet may be fraudulentlyrepeated).

Additionally, in legacy networks, a STA may send a single acknowledgmentrelated to a block of a plurality of frames. This process may bereferred to as BA operation. Typically, a STA will only transmit a BAframe in legacy networks when requested by an AP. Such a request may bebased on a “BlockAckReq” message transmitted from the AP and received bythe STA.

In the legacy networks, the SN use for duplicate detection for the groupaddressed frames has not been considered relevant, because AP hastransmitted each group addressed frame only one time. For groupaddressed frames and individually addressed frames without block-ackagreement, the SN based duplicate detection has been done only to theframes that have Retry field in MAC Header set to 1, i.e. duplicatedetection is done only to the frames that are retransmitted. The legacyacknowledgement scheme assumes that transmitter transmits only a singleunicast frame in a SNS, and the transmitter will proceed to thetransmission of the frame with a higher SN value only after it hasreceived an acknowledgment (ack) for the previously transmitted frame,or has decided to discard that previously transmitted frame.

In a WLAN network that uses the block-ack scheme for unicast dataframes, the receiver agrees to keep a record of receive status for somenumber of SNs (received, not received), and is capable to send block-ackto signal the status of the received frames and to reorder the frames inthe SN order before the frames are forwarded to the application. The SNspecific knowledge on whether a frame is already received or not allowsthe receiver to detect duplicate frames even if the Retry field in theMAC header is not set to 1 for a frame.

In a network containing MLDs, the AP MLD 152 transmits a copy of groupaddressed data frames from each AP 1262, 164, 166 to allow the legacySTAs associated with each AP to receive these frames and for otherconsiderations (e.g., simple power save management). The non-AP MLDneeds to receive these group frames only once, so it may select fromwhich AP it receives the frames. The transmitting AP may use SNS1 forall transmitted legacy unicast data frames (non-QoS data), allmanagement frames and group frames, and the SNS1 used by a particular AP(e.g., AP1 162, AP2 164, AP3 166) is independent from the SNS1 used byother APs of the same AP MLD.

The use of an SNS for each communication link may result in errors in acommunication network such as communication network 100 because,although each link may be assigned an SNS, the SNS for each link may notbe globally unique. That is, two links may include overlapping SNs. Onesuch error may therefore be referred to as a “false negative” That is,the STA may receive the same frame or the same packet on different linkswith different SNs. In this situation, the STA may not identify that thepacket is a duplicate, because such identification may be based on theSN of the packet.

Another error may be referred to as a “false positive.” That is, the STAmay receive different frames or packets on different links, but thedifferent frames or packets may include the same SN. In this situation,the STA may falsely identify, based on the SN, that the packets areidentical and discard a valid packet.

In addition, a PN may be added to the packets by the encryption key. ThePN may be specific to encryption key. Typically, the SN may be used todelete duplicated packets and, if block acknowledgement is in use, thereorder buffer may arrange received packets belonging to the BAagreement into SN order. At the decryption of the received frames, thedecrypted frames may have increasing PN. Frames that have smaller orequal PN value than an already decrypted frame may be discarded. Thisanalysis at decryption may ensure that received packets are not areplayed version of a previous frame.

When the transmitter and receiver have not established a BA agreement,then the frames may be transmitted in the increasing SN and PN order.The unicast frames that use acknowledgement may not proceed to the nextframe until they get acknowledgement to the previous frame. Proceedingto the next transmitted frame may cause PN update and the loss of theprevious frame. This is because, a frame with a smaller PN value, evenif it is retransmitted, will be considered a replay attack and deletedupon decryption. Similarly, the group addressed frames always haveincreasing PN values. In legacy networks, the group addressed frames aretransmitted by an AP, which simplifies their PN handling.

FIG. 3 depicts an example of SNS1 conflicts in a wireless network 300containing MLD, in accordance with various embodiments. Specifically, asmay be seen, various data may be provided from an AP MLD 302 (which maybe, for example, similar to AP 110 b of FIG. 1A) to a non-AP MLD 304(which may be similar to, for example, STA 120 f). Such data mayinclude, for example:

Non-QoS unicast data frames 306 (referred to herein as U-Data (non-QoS)frames);

Non-QoS Groupcast frames 308 (GCFs) (referred to herein as G-Data(non-QoS) frames); (As described herein, the term “groupcast frames” isused interchangeably with the term “group addressed frames”).

QoS GCFs 310 that include GCR frames (Referred to herein as G-Data (QoS)frames);

Unicast management frames 312 that are generated at the multi-link (ML)level, for example by the ML entity 330 of MLD AP (such as access point110B in FIG. 1A) (referred to herein as U-Mgmt (ML) frames);

Group cast management frames 314 generated at the ML level, for exampleby the ML entity (referred to herein as G-Mgmt (ML) frames);

Group cast management frames 316 generated at the local level, forexample by AP1 or AP2 (referred to herein a G-Mgmt (Local) frames); and

Unicast management frames 318, generated at the local level, for exampleby AP1 or AP2 (Referred to herein as U-Mgmt (Local) frames).

As may be seen in FIG. 3 , AP1 324 and AP2 326 may respectively generatethe local-level data (e.g., G-Mgmt (Local) and U-Mgmt (Local)). Further,the non-local data such as U-Mgmt (ML), U-Data (non-QoS), G-Data(non-QoS), G-Data (QoS), and G-Mgmt (ML) may be generated at the levelabove and passed to AP1 324 and AP2 326.

AP1 324 then transmits the data over link 1 to a legacy STA 320 (STA A)and non-AP MLD B. Similarly, AP2 326 transmits the data over link 2 to alegacy STA 322 (STA C) and non-AP MLD B. However, because the same data,or the different types of data using SNS1 332 a, 332 b, is transmittedfrom AP1 324 over link 1 and from AP2 326 over link 2, and the SNS1 332a, 332 b is maintained by a particular AP (e.g., AP1, AP2), the data maycreate a false positive or a false negative as described above.Specifically, as shown in FIG. 3 , the G-Data (QoS) 310, G-Data(non-QoS) 308, G-Mgmt (ML) 314, G-Mgmt (Local) 316, and U-Mgmt (ML) 312may be received from both AP1 324 and AP2 326 by the non-AP MLD B.Because the same GAF data, or the different types of data using SNS1 332a, 332 b specific to an AP (e.g., AP1, AP2), is received from twosources, one or both of a false positive or false negative may beidentified for one or more of the data as described above.

TID-Agnostic GCR-BA

Generally, FIG. 4 describes a network 400, similar to network 300, inwhich multiple new sequence number spaces that all operate in ML level.General transmission rules are used for group frames, and the GCR BAoperation, if used, is TID-agnostic. FIG. 5 describes a network 500,similar to networks 400 and 300, including a scenario where the GCR BAoperation is TID specific. One transmitted frame belongs to exactly oneSN space, and 802.11 specification specifies to which SN space the framebelongs.

More specifically, FIG. 4 depicts an example of use of a shared SNS, inaccordance with various embodiments, which may resolve one or more ofthe above-described conflicts. In this embodiment, an SNS 402 (referredto herein as SNS_new) is defined for Link 1 and Link 2. SNS_new 402 hasthe same SN for the frame with the same data content in both links 1 and2. The SNS_new 402 may be generated or managed by the ML entity. Morespecifically, the ML entity may be an element of the AP MLD.

The SNS_new may be used for one or more of the conflicting framesdescribed above. Specifically, as shown in FIG. 4 , SNS_new 402 may beused for the transmission of the G-Data (QoS) frames 310 (which mayfurther include GCR frames), G-Data (non-QoS) frames 308, G-Mgmt (ML)frames 314, G-Mgmt (local) frames 316, and U-Mgmt (ML) frames 312.SNS_new 400 may further be used for transmission of U-Mgmt (Local) MLDframes 318, which are U-Mgmt (Local) frames that pertain to the non-APMLD B 304. As shown in FIG. 4 , SNS1 332 a, 332 b may still be used forthe transmission of U-Mgmt (Local) frames and U-data (non-QoS) and fromAP1 324 or AP2 326. Alternatively, SNS1 332 a, 332 b may still be usedfor the transmission of U-mgmt (Local) frames whose recipient is alegacy single-link STA and the U-data (non-QoS), while the transmissionof U-mgmt (Local) frames 318 whose recipient is a non-AP MLD STA use theSNS_new 402.

In this embodiment, the G-Data (QoS) 310 may include bothno-Ack/no-retry groupcast (GC) and GCR (Groupcast with Retries) frames.No-Ack/no-retry GC and GCR frames may be frames that are related totransmissions to a legacy STA such as STA A 320 and STA C 322 as well asa MLD STA such as STA B 304. Certain of the STAs 320 (e.g., STA A) maybe a legacy STA that is incapable of using the GCR protocol. Another ofthe STA 322 (e.g., STA C) may be a legacy STA that is capable of usingthe GCR protocol. In this embodiment, STA A 320 would ignore the GCRframes due to the concealment address employed by the GCR frames, whichis a field that prevents group-addressed frames transmitted via GCR frombeing identified/used by GCR-incapable STAs. STA C 322, by contrastwould filter out duplicated GCR frames based on concealment address anddestination address (DA), as well as address 2, SN, Retry field valueindicated in the frame.

It will be noted that in this embodiment, the GCR BlockAckReq may have afixed traffic identifier (TID) value. The value may be, for example, avalue of “0.” Because the TID has a fixed value, this embodiment may bereferred to as TID-Agnostic GCR-BA, and may be generally similar inbehavior to GCR-BA defined for a single link operation.

Further, the non-AP MLD 304 (e.g., non-AP MLD B) may perform duplicatedetection across multiple links (e.g., Link 1 and Link 2). Specifically,because the same frames (e.g., G-Data (QoS) 310, G-Data (non-QoS) 308,etc.) may share the same SNS 402 (e.g., SNS_new) across all links, thenthe SN of identical frames that are received over Link 1 and Link 2 isidentical. The non-AP MLD B 304 uses the SN of a groupcast framereceived over link 1 and the SN of a groupcast frame received over link2 to identify whether the two frames are duplicates. For GCR frames, inaddition to use address 2, SN, the retry bit value of the frames, anon-AP STA also uses address 1 (concealment address) for duplicatedetection.

In this embodiment, for GCR unsolicited retry, a frame subject to theGCR agreement may also be sent using a legacy no-Ack/no-retry protocolif one or more of the STAs receiving the group address does not have aGCR agreement with the AP to which it is coupled (e.g., AP1 or AP2). Asa result, it may be difficult to use different SNSes for GCR unsolicitedretry (QoS) and non-GCR G-Data. However, because the GCR-BA policy maybe active only when all STAs receiving the group address have a GCR-BAagreement with the AP, it may be possible to use one SNS for GCR-BArelated G-Data (QoS) frames (referred to herein as GCR-BA G-Data (QoS)frames) and another SNS for the non-GCR-BA-related G-Data (QoS) frames.Further, it may be possible to allow multiplicity for TID-specific SNSfor GCR-BA G-Data (QoS) frames, as described below.

TID-Specific GCR-BA

FIG. 5 depicts an alternative example of use of a SNS that is sharedacross all links (e.g., link 1, link 2), in accordance with variousembodiments. Specifically, FIG. 5 depicts an alternative example of useof a TID-specific SNS for GCR-BA frames 504. As may be seen in FIG. 5 ,this example may be generally similar to the embodiment of FIG. 4wherein the SNS_new 502 (referred to in FIG. 5 as SNS_new_1) is sharedacross all links (e.g., Link 1 and Link 2), and is used for the U-Mgmt(ML) frames, G-Mgmt (ML) frames, G-Data (non-QoS) frames, and G-Mgmt(Local) frames, G-Data (QoS) frames (include legacy no-Ack/no-retryframes and GCR unsolicited retry (QoS) frames), U-mgmt (Local) whoserecipient is a non-AP MLD. As shown in FIG. 5 , SNS1 332 a, 332 b maystill be used for the transmission of U-data (non-QoS) and U-Mgmt(Local) frames whose recipient is a legacy STA and from AP1 or AP2.Alternatively, SNS1 332 a, 332 b may still be used for the transmissionof U-mgmt (Local) frames whose recipient is either a legacy single-linkSTA or a non-AP MLD and the U-data (non-QoS).

In this embodiment, the G-Data (QoS) frames, which use the SNS_new_1502, may not include GCR-BA related frames. Rather, a separate SNS(referred to in FIG. 5 as SNS_new_2 (shared) 506) may be used for GCR-BAG-Data (QoS) frames. Specifically, the SNS_new_2 (shared) 506 may be aSNS that is shared across all links (e.g., Link 1 and Link 2), and isused for transmission of GCR frames subject to a GCR-BA agreement.

As noted, the SNS_new_2 (shared) 506 may be shared across a plurality(or all) of the links, which may allow for multiplicity and is indexedby <address 1, TID>. In other words, there may be multiple TID values,and so there may be multiple SNS_new_2 maintained by the transmitter foreach address 1. Accordingly, the GCR BlockAckReq may be modified to beTID-specific.

In some embodiments, the SNS_new_2 506 may be similar to SNS type 2(SNS2) as defined in the Institute of Electrical and ElectronicsEngineers (IEEE) 802.11 standard for unicast QoS data. As analternative, the SNS_new_2 506 may be merged with SNS2. In other words,the SNS2 may be modified such that it is used by both unicast QoS data(referred to herein as U-Data (QoS)) and GCR-BA frames. Doing so mayallow for multiplicity, and may be indexed by the “address 1” and TID ofthe frame.

Other SNS Design Variants

For both the SNS design related to the TID-Agnostic GCR-BA (as describedwith respect to FIG. 4 ) and the SNS design related to the TID-specificGCR-BA (as described with respect to FIG. 5 ), SNS_new or SNS_new_1 maycontain a set of SNSes, where each SNS is specific to a receiver address(group or individual address), frame type and/or QoS level, and thetransmission of one frame uses the corresponding SNS. For duplicationdetection, in addition to using SN, a receiver may also use otherinformation, such as frame type, and/or Link ID, etc.

As an example, an additional SNS that is shared across all links and isused only for U-Mgmt. This SNS may be referred to as “SNS_new_x(shared).” The SNS_new_x (shared) may allow for multiplicity, and may beindexed by one or both of an address field (e.g., “address 1 (i.e.,receiver address)”) and a frame type (e.g., the “frame type” field). Inthis embodiment, a receiver (e.g., a non-AP MLD such as non-AP MLD B)may use one or more of the frame type field, the “address 2 (i.e.,transmitter address)” field, SN as well as other information (e.g., LinkID) for frame duplicate detection.

GCR-BA Over Multiple Links

As noted above, it may be desirable for GCR-BA to be performed overmultiple links. Therefore, it may be desirable for a GCR-BA agreement(per concealment address) to be established at the MLD level in a mannersimilar to that of a unicast-BA agreement. Specifically, the use of aGCR service period (GCR-SP) frame technique may be modified such that,if all members of the GCR-BA group are awake (i.e., not asleep) at aparticular time, then an AP MLD (e.g., an AP that has multiple linkswith a non-AP MLD) may deliver the GCR frames immediately withoutwaiting for a pre-defined deliver traffic indication map (DTIM) beacons.The modified GCR-BA procedure to allow the use of GCR-BA over multiplelinks may take the form of one (or both) of the two following modes.

Mode 1

Mode 1 may relate to the situation that all members of a GCR-BA groupreside on the same link for the GCR operation. In this embodiment, aframe subject to a GCR-BA agreement is sent only on the link between theAP MLD and the non-AP MLD where the recipient STAs reside. The AP MLDmay transmit the GCR frames and the BlockAckReq frame, and receive theBA (Block Ack) frame on this operating link. The AP MLD may thendetermine which, if any, aggregate MAC service data units (A-MSDU) toretransmit based on one or both of a BA bitmap from each member of thegroup and a missing BA frame. This Mode may generally be seen asinvolving GCR-BA operation over MLD in a manner similar to that ofunicast-BA operation over MLD.

Mode 2

Mode 2 may relate to a situation in which members of the GCR-BA groupsreside on different links for the GCR operation. FIGS. 6 and 7 depicttwo options for this Mode. Specifically, FIG. 6 depicts an example of aprocedure 600 related to GCR-BA over multiple links, in accordance withvarious embodiments. FIG. 7 depicts an alternative example of aprocedure 700 related to GCR-BA over multiple links, in accordance withvarious embodiments.

In FIGS. 6 and 7 , an AP MLD may be coupled with a plurality of non-APMLDs (e.g., non-AP MLDs A, B, and C) over a plurality of links (e.g.,link 1, link 2, and link 3) as described above with respect to, forexample, FIG. 1B. Specifically, as shown, AP MLD may communicate withnon-AP MLD A over links 1 and 2. AP MLD may further communicate withnon-AP MLD B over links 2 and 3. AP MLD may further communicate withnon-AP MLD C only over link 3. Please note that the behavior of a legacySTA that associates to one of the APs of the AP MLD and participates inthe GCR-BA operation is similar to that of Non-AP MLD C.

In this embodiment, a data frame subject to a GCR-BA agreement may besent independently (i.e., repeated) on all links of a MLD where theGCR-BA group members reside. Then, the AP MLD may send, to each non-APMLD in the GCR, a BA Request (BAReq), which may be an explicit requestfor the non-AP MLD to transmit a BA related to the data frame.

FIG. 6 shows one option by which the BAReq frame may be sent.Specifically, the AP MLD may select a single link on which to send aBAReq to a non-AP MLD. For example, the BAReq related to non-AP MLD A,indicated as BAReq_A, is transmitted on link 1. The BAReq related tonon-AP MLD B, indicated as BAReq_B, is transmitted on link 2. The BAReqrelated to non-AP MLD C, indicated as BAReq_C, is transmitted on link 3.

FIG. 7 depicts an alternative option wherein the AP MLD transmits theBAReq frame related to the non-AP MLD on every link over which the APMLD and the Non-AP MLD are communicatively coupled. For example, theBAReq_A (i.e., the BAReq sent to non-AP MLD A) is transmitted over links1 and 2. BAReq_B (i.e., the BAReq sent to non-AP MLD B) is transmittedover links 2 and 3. BAReq_C (i.e., the BAReq sent to non-AP MLD C) istransmitted over link 3.

In either of the embodiments indicated in FIG. 6 or 7 , the BA frame maythen be transmitted from the non-AP MLD to the AP MLD over the link onwhich the corresponding BAReq frame is received. Generally, each BAReqframe solicits a BA frame as a response. The BAReq frames transmitted onone link to different non-AP MLDs may have different receive address.

A non-AP MLD (e.g., non-AP MLDs A, B, or C) may filter out duplicate GCRdata frames that are received on different links. An AP MLD may deriveMLD-level composite bitmaps based on one or more of the bitmaps in theBA frames received on each link from the GCR members and one or moremissing BA frame(s). Based on the MLD-level composite bitmap of allmembers of the GCR-BA group, the AP MLD may decide to transmit or retryan A-MSDU.

In one embodiment, when members of a GCR-BA group reside on differentlinks, they may be able to switch to a common link at the GCR-BA framedelivery time for the GCR operation. In this embodiment, even though themembers of the GCR-BA group were initially identified as being ondifferent links (and therefore, Mode 2 may be appropriate), the switchto a single link may therefore make Mode 1 more appropriate.

GCR BlockAckReq Variant for TID-Specific GCR-BA

The legacy IEEE 802.11 standard, describes a variant BlockAckReq forGCR. In that variant, the TID_INFO field may be set equal to 0. However,in embodiments herein where the GCR-BA is TID-specific (as describedabove with respect to FIG. 5 ), it may be desirable to unify themulti-link BA operation for both unicast and group cast. In thisembodiment, the GCR BlockAckReq may be TID-specific, i.e., the TID_INFOfield may not always be set to 0.

This embodiment may be performed in one of two ways. In the first, theexisting GCR BlockAckReq variant defined in the legacy standard may beredefined. Alternatively, a new GCR BlockAckReq variant may beintroduced that allows for the TID_INFO field to be set to a value otherthan 0. Such a variant may have a name such as “TID-Specific GCRBlockAckReq variant.”

For both of these options, the GCR BlockAckReq variant may be used for asingle BlockAckReq or to request BA for multiple TIDs.

GTK and PN

A wireless network may use a GTK to encrypt or decrypt multicast andbroadcast traffic between an AP STA and a non-AP STA. A pairwisetransient key (PTK) may be used to encrypt or decrypt traffic between asingle AP and a single STA. For MLD, a single PTK and a single PN may beused across all links for unicast, while different GTKs may be used foreach link for groupcast.

FIG. 8 depicts an example of GTK and PN check design 800 for use withmultiple links, in accordance with various embodiments. In theembodiment of FIG. 8 , the BA design may be unified for both (a)unicast-BA operation over MLD and (b) the GCR-BA operation over MLD.Specifically, a single PTK and PN may be used across all links, and asingle GTK, which is generated at the ML level and is referred to inFIG. 8 as “GTK-ML” may be used for all links. In this embodiment, the PNcheck may be performed by the non-AP MLD at the ML level.

Group Frames Reception on Multiple Links

FIG. 9 depicts an example of group frame reception 900 on multiplelinks, in accordance with various embodiments. As previously discussed,the PN number of the group frames may prevent reception of the groupframes that have smaller PN number. In case the group addressed frameshave an SN space that is dedicated only for group addressed data frames,then this new SNS can have the SN value for a group addressed frame inall links. The AP may continue to use SNS1 for the unicast managementframes generated by the APs (i.e., AP1, AP2) locally (i.e., notgenerated at the ML level) and unicast non-QoS data frames, or the APmay introduce receiver-specific SNSs to transmit these frames.

A separate copy of each group addressed data frame or group addressedmanagement frame may be transmitted on each link, which allows a non-APMLD to receive group frames only from a single link, in order to simplythe power save operation of the non-AP MLD. The non-AP MLD may selectthe link from which it receives the group addressed frames and thenon-AP MLD does not need to determine whether different links havedifferent buffered group frames.

Transmitting a copy of a group frame in all links is not a fullyaccurate definition in all cases. Some group management frames and groupdata frames may be link specific. For instance, an AP may broadcast BSSTransition Management (BTM) request frame that requests all STAs thatare associated to the AP to move to another AP, or alternatively, an APmay broadcast an Extended Channel Switch Announcement Frame that signalsthat AP will switch to operate in a different channel. If thesemanagement frames are transmitted by other APs affiliated with the APMLD, then the information is relevant only to non-AP MLDs that havesetup multi-link with the AP MLD but irrelevant to the legacy STAsassociated to the AP of an AP MLD.

In addition, link specific group addressed data frames may be needed byservice discovery protocols. For example, universal Plug and Play (UPnP)or Bonjour are used to allow local devices to offer services bytransmitting group addressed data frames that carry service discoveryinformation of the available services. Sometimes, a service may beavailable only through a specific AP. For instance, an application mayuse high transmission capacity that is supported by the 5 or 6 GHz bandsbut not supported by the 2.4 GHz band. In these cases, the servicediscovery information may be available for legacy STAs through APsoperating in 5 GHz and 6 GHz bands and for non-AP MLDs over all links,but irrelevant to the legacy STAs associated to the APs operating on the2.4 GHz band, and therefore should not be received by the legacy STAsoperating on the 2.4 GHz band. Please note, there are other examples.

The AP MLD needs to have means to transmit these group addressedmanagement frames and group addressed data frames so that legacy STAscan receive the frames only from a single AP or from subset of APs, butnon-AP MLDs can receive the group addressed frame in all links. Thereare multiple ways to make the DL (downlink) group addressed framereceivable only by the non-AP MLDs. For instance, AP may transmit thegroup addressed frame in a physical layer protocol data unit (PPDU)format that is receivable only by the non-AP MLDs.

In other embodiment, the AP may add a new frame type to piggy back theold DL group frame. This new frame type is understood only by the non-APMLDs and the legacy STAs are not able to understand the frame content.

The new PPDU type and new frame may contain information that identifiesthe AP(s) in AP MLD that is group casting the legacy receivable frame orit may identify the AP(s) that transmit the frames that are onlyreceivable by the MLDs but not the legacy STAs.

In an embodiment, the AP may transmit link specific individuallyaddressed management frames to a non-AP MLD. To reduce implementationoptions, the AP may carry the management frame in the new type ofmanagement frame that is receivable only to non AP MLDs. The newmanagement frame signals also the AP in AP MLD and/or the STA in non-APMLD that operate in a link to which the link specific management framecarries signaling information. For instance, AP2 in AP MLD may unicastto the STA2 in non-AP MLD the new management frame type carryingmanagement information for the link in which the AP1 in AP MDL and STA1in non-AP MLD operate. Please note that unicasted management frames arereceived by a single addressed STA. The use of the same new MPDU typereduces need to have a separate solution to unicast information onanother link.

In one embodiment, the AP MLD may unicast a copy of all or selectedgroup addressed frames to a non-AP MLD. If such link specific groupaddressed management or data frame is unicasted, the AP applies the samenew frame type, if the information is targeted for another AP in AP MLD.

The non-AP MLD may transmit an UL (uplink) unicast frame that requestsAP MLD to DL group cast the UL frame to associated STAs in AP MLD.Currently, AP broadcasts the UL frame in all APs of the AP MLD.

The non-AP MLD may have new signaling in the UL unicast frame thatsignals to AP the set of APs in which the frame should be group castedin legacy receivable format. For instance, the UL unicast frame mayinclude a control field that signals the links to which the frame willbe group transmitted in a format that is receivable for legacy STAs. Inone embodiment, the control field may be the A-Control field in the MACHeader. The AP will group cast the group frame in other links so that itis receivable only to non-AP MLDs.

The AP may parse the UL unicast frames that contain a frame that will beDL group casted by the AP. If the AP detects that UL unicast framecontains service discovery information, the AP may automatically groupcast the frame in legacy STA receivable format only in the AP in whichthe frame was received and group cast the frame in non-AP MLD receivableformat in other links. In some embodiments, the AP may have a logic todecide the transmission resource needs of the applications that areadvertised in the service discovery information and group cast theservice discovery information in the legacy receivable format in APsthat have enough capacity to be able to operate the advertisedapplication and other ongoing traffic in acceptable QoS level.

In FIG. 9 , a non-AP MLD may receive frames on a plurality of links(each indicated by “link Specific receiving (RX) 902 a-c”). The groupdata frames may be provided to a Group Frame Reorder buffer 904, whichmay perform duplicate frame detection and missing frames detection bychecking SN of the received frames. The Group Frame Reorder buffer 904may further eliminate duplicated frames. In some embodiments, if thenon-AP MLD receives group frames from a single AP over a single link itmay not need, or may not use, a Group Frame Reorder buffer.

The Group Frame Reorder buffer 904 may not need any setup signaling, itssize and use of such buffer may be receiver specific operations. Inother embodiments, the non-AP MLD may signal the size of its Group FrameReorder buffer 904 and the number of SNSs to which it may have GroupFrame Reorder buffers. The number of Group Frame Reorder buffers mayhelp AP MLD to decide the number of QoS levels it uses to transmit groupframes.

After processing the duplicates, the Group Frame Reorder buffer mayprovide the frames to the PN Check and Decryption block 906 based on oneor more conditions. In some embodiments, if all links use the same GTK,the PN check and decryption may be done only after reordering, otherwisepossible higher PN from other link may prevent frames decryption. Insome embodiments, the reordering should be done regardless whether thegroup data frames are encrypted with a same GTK in all links or withlink specific GTKs.

Individually addressed frames may be selectively retransmitted. In thisoperation, a BA typically identifies the SN of the MAC protocol dataunit (MPDU) which is received. All other SNs are either not received ornot transmitted. Such selective retransmission may not be available forgroup frames that are transmitted one time over each link. The receivermay keep link specific SN counter for the received data frames. If alink specific SN is higher than missing frame in a link, then thereceiver knows that it will not receive the missing from this link.

In one embodiment, the receiver checks the link specific SN value onlyafter DTIM beacon when it has received the group addressed frames. Insome AP implementations, the group frames transmission may not beperformed exactly in the SN order, but the set of frames transmittedafter the DTIM beacon should be within the SN range.

In one embodiment, the STAs associated to the AP are all in active modeand AP may send group addressed frames as soon as possible, withoutwaiting for the DTIM beacons. In this case, a STA may apply some delayafter which it considers the SN of the received group addressed frame asthe link specific SN value.

As discussed earlier, group addressed data frames may be transmittedwith the QoS priority levels defined by the User Priority field in theMAC Header. The QoS data frames may belong to multiple SNSs and thereceiver may maintain multiple link specific values, one per SNS.

FIG. 10 depicts an example of this condition. Specifically, FIG. 10depicts an example of frame processing by a Group Frames Reorder buffer,in accordance with various embodiments. FIG. 10 shows group framesreception status in three links X, Y and Z. The Upper line shows anexample situation, where the receiver has received different groupframes from different links. The highest SN of the received group frameshave different values. The FIG. 10 shows an example operation where thereceiver receives group frames form link X. The bitmap indicates statusof the received group frames. Value 1 in the bitmap signals that a framewith the matching sequence number is received by the STA and value 0indicates that STA has not received the frame with the matching sequencenumber. If all links have passed a SN of a frame that is not received,then the receiver may identify that this group frame will not betransmitted any more through any link and the STA needs to consider thisgroup frame as lost. For instance, in the scenario 1000 of FIG. 10 , thefirst two group frames with the lowest SN, i.e. the leftmost values 0,are received in link X, the frames with fourth and fifth lowest SN arenot received, and the frame with sixth lowest SN is received. Thus, thereorder buffer is missing the frame with fifth lowest SN, but becausethis frame cannot be received from any link, the reorder buffer mayleave a hole on received group frames and forward the received packetsto the PN check and decryption.

As another condition, the receiver may decide that it prefers to reduceits power consumption and only receive group frames from other links, ifthe group frames leave large holes to SN. For instance, STA may acceptloss of one or two group frames per DTIM period.

Another condition may be related to a received frame that does not fitto the reorder buffer. In this situation, the frames with the lowest SNmay be forwarded to the PN Check and Decryption to make space for newlyreceived frames.

After processing, the PN Check and Decryption block 906 may output theframes to an application 908 for further processing. It will beunderstood that the embodiment depicted in FIG. 9 is intended as ahighly simplified example embodiment. One or both of the Group FramesReorder buffer and the PN Check and Decryption block 906 may beimplemented as hardware, software, firmware, or some combinationthereof.

For a non-AP MLD, it is difficult to change the AP from which the groupaddressed frames are received, if the SNs of multiple APs of an AP MLDare not coordinated. The only safe time to change the AP from which theSTA receives group frames is when the current and new AP have nobuffered traffic. Deciding such period may be complicated and if non-APMLD operates multiple radios, it may not be able to wait for suitabletime.

The same SN use for all group frames without GCR or other deliveryenhancements also simplifies group frames reception in non-AP MLD. TheSTA can switch the AP from which it receives group frames without riskof duplicate frames being forwarded to the application 908.

If a non-AP MLD is saving power, it is likely that group addressedframes are received from a single AP. If the STA is changing the AP fromwhich it receives the group addressed frames, it is recommended totemporarily receive group addressed frames from two APs. This ensuresthat STA receives all group addressed frames. If the STA detects the SNof the received group frame from new AP to be smaller than SN receivedfrom the current AP, then the STA may transition immediately. If the SNof the group frame is larger than received from the current AP, then theSTA should continue to receive group addressed frames from the currentAP to receive all group addressed frames.

If the old AP transmits group frames after DTIM beacon, good candidateswitch time to receive group frames from new AP is right after all groupframes are transmitted. In many implementations, the AP transmits groupframes continuously. The non-AP MLD may detect that AP transmitted allgroup addressed frames, if the STA detects unicast frame transmissionfrom the AP, or the STA detects idle period (no transmission from theAP) in the channel.

GCF Transmitted Using MLD_address

In some embodiments, it may be desirable to transmit an additional copyof the GCF using an MLD_address of the AP MLD as the transmit address,in addition to the GCFs transmitted using the MAC address of a specificAP (e.g., AP1, AP2) as the transmit address. FIG. 11 depicts an exampleof this embodiment 1100. Specifically, FIG. 11 depicts an example ofusage of GTK and PN space for two copies of GCF transmitted usingMLD_addresses and AP_i's MAC address, respectively, in accordance withvarious embodiments. By receiving only the copy of GCFs with thespecific transmit address (e.g., legacy STAs only receive the copy withthe MAC address of a specific AP as the transmit address) and filteringout/discarding the copy with other transmit address (e.g., legacy STAsfilter out/discard the copy with the AP MLD address as the transmitaddress), such methods will eliminate the duplicate detection errors(both “false positive” and “false negative” cases as described earlier)for both legacy STAs and non-AP MLDs. The details of such methods aredescribed below.

As may be seen in FIG. 11 , and as briefly described previously withrespect to FIG. 1B, an AP MLD 1108 may be communicatively coupled with anon-AP MLD 1106 by a plurality of links 1110 a-c. Additionally, a numberof APs 1102 a-c (AP1, AP2, and AP3) may be coupled with a number of STAs(e.g., STA1, STA2, and STA3). The AP MLD may have an MLD_address, andthe non-AP may have an MLD_address. The respective APs may haverespective basic service set identifier (BSSIDs), which may be the MACaddresses of the APs. Similarly, the respective STAs may haveover-the-air (OTA) mac addresses (OTA MAC1, OTA MAC2, OTA MAC2), whichare the MAC addresses of the STAs 1104 a-c.

In this embodiment, the respective APs 1102 a-c and STAs 1104 a-c maycommunicate over their respective links using a GTK (e.g., GTK1, GTK2,GTK3 or GTK-ML (i.e., GTK generated at the MLD level)). Meanwhile, theAP MLD and the Non-AP MLD may communicate across all links using asingle GTK-ML and using a single groupcast PN (PN_gc) space. In additionto transmit the GCFs on each link using the corresponding address ofAP_i (“i” is the link index) as the transmit address (i.e., address 2 ofthe frames), GCFs are also transmitted over all links using theMLD_address as the transmit address (i.e., address 2 of the frames).

The following example behaviors depicted in Table 1 may be exhibited onthe transmit side. The behaviors may be relevant to, for example, theembodiment of FIG. 4 wherein the system uses SNS_new 402. As used inTable 1 (and other tables in this section), transmit address (TA) mayrefer to the transmit address in the GCF.

TABLE 1 Transmission of additional copy of GCF using MLD_address UseSNS_new (as defined, for example, Link(s) Encryption with respect totransmitted Key FIG. 4) GCF with TA = Transmit GTK-ML Yes. A single SNSis MLD_address all links shared across all links for the GCF GCF with TA= Link_i GTK_i or Transmission on AP_i_address GTK-ML link_i uses itsown SNS1_i as defined in the IEEE 802.11- 20016 specification. Thispreserves legacy behavior.

Similarly, the following example behaviors depicted in Table 2 may beexhibited on the receive side.

TABLE 2 Reception of additional copy of GCF using MLD_address Actiontaken by non- Action taken by AP MLD (e.g., Legacy STA MLD_STA) GCF withTA = Filter out/discard the Receive the GCF MLD_address GCF (based onthe TA or the SA (source address)) GCF with TA = Receive the GCF Filterout/discard the AP_i_address GCF (based on TA)

In some embodiments, for example, the embodiment depicted with respectto FIG. 5 , it may be desirable to additionally create an SNS that isspecifically related to BA for GCA. This SNS may be referred to hereinas SNS_GCA_BA (shared). This SNS may be shared across all links, and maybe used to transmit GCFs that are subject to a GCR_BA agreement. Use ofthe SNS_GCA_BA (shared) may allow for multiplicity, and may be indexedby the “address 1” field of the frame and/or the TID. In anotherembodiment, the SNS_GCA_BA (shared) may be merged with SNS2 as describedabove with respect to the embodiment of FIG. 5 . In this embodiment, thefollowing example behaviors depicted in Table 3 may be exhibited on thetransmit side, and the example behaviors depicted in Table 2 may beexhibited on the receive side.

TABLE 3 Transmission of additional copy of GCF using MLD_address Link(s)Encryption SNS_new transmitted Key used? SNS_GCA_BA GCF with All linksGTK-ML Yes. A single Yes. An SNS is TA or SA = SNS shared shared acrossMLD_address across all all links for the links for the transmission ofGAF, except frames subject GCA_BA to GCA BA frames agreements. GCF withLink_i GTK_i or Transmission Transmission TA or SA = GTK-ML on link_iuses on link_i uses AP_i_address its own its own SNS1_i space, SNS1_ispace, as defined in as defined in the IEEE the IEEE 802.11-2016802.11-2016 specification. specification. In this way, In this way,legacy legacy behavior may behavior may be preserved be preserved

FIG. 12 depicts a flow diagram showing an example process 1200 for groupaddressed frame delivery over multi-link systems. The process 1200includes identifying (1202), by an access point (AP) multilink device(MLD) in a wireless network, a first sequence number space (SNS) that isto be used by the AP MLD to transmit data to a non-AP MLD over a firstcommunications link and a second communications link. Frames withidentical data that are transmitted over the first and secondcommunications links will have an identical first SN based on the firstSNS. In some implementations, the first frame is a frame related togroupcast data (G-Data) for quality of service (QoS), groupcast withretry (GCR) data, G-Data not requiring QoS, groupcast management datagenerated at the multilink (ML) level, Groupcast management datagenerated by the first AP, unicast management data generated at the MLlevel, and possibly unicast management data generated by the AP and isintended for the non-AP MLD.

The process 1200 includes identifying (1204), by the MLD in the wirelessnetwork, the first SN based on the first SNS. In some implementations,the SNS is independent of a traffic identifier value (TID) of the firstframe for GCR-BA operation.

The process 1200 includes transmitting (1206), by the AP MLD in thewireless network, a frame that includes the data to the non-AP MLD basedon the first SN.

In some implementations, the process 1200 includes identifying, by theMLD in the wireless network, a second SNS that is to be used by the MLDto transmit groupcast with retry block acknowledgment (GCR-BA) data overthe first communications link and the second communications link,wherein identical frames on the first and second communications linksthat include identical GCR-BA data will have an identical second SNbased on the second SNS. In some implementations, the process 1200includes identifying, by the MLD in the wireless network, the second SNbased on the second SNS. In some implementations, the process 1200includes transmitting, by the AP MLD in the wireless network, a framethat includes the GCR-BA data to the non-AP MLD based on the second SN.

In some implementations, the identification of the second SNS is basedon a value of “address 1” of the frame that includes the GCR data. Insome implementations, the second SNS is indexed by a traffic identifier(TID) value of the frame that includes the GCR data.

In some implementations, the process 1200 includes identifying, by theMLD in the wireless network, a third SNS that is to be used by the MLDto transmit unicast management data over the first and secondcommunications links, wherein identical frames on the first and secondcommunications links that include identical unicast management data willhave an identical third SN based on the third SNS, where theidentification of the third SNS is based on a value of “address 1” andframe type of the frame. The process 1200 can include identifying, bythe MLD in the wireless network, the third SN based on the third SNS.The process 1200 can include transmitting, by the AP MLD in the wirelessnetwork, a frame that includes the unicast management data to the non-APMLD based on the third SN.

FIG. 13 depicts a flow diagram showing an example process 1300 for groupaddressed frame delivery over multi-link systems. The process 1300includes identifying (1302), by an access point (AP) multilink device(MLD) in a wireless network, a data frame that is to be transmitted to aplurality of non-AP MLDs subject to a groupcast with retry (GCR) blockacknowledgement (BA) agreement. The process 1300 includes identifying(1304), by the AP MLD, respective communication links by which the APMLD is communicatively coupled with the non-AP MLDs. The process 1300includes transmitting (1306), by the AP MLD, the data frame on each ofthe respective communication links. The process 1300 includestransmitting (1308), by the AP MLD based on the transmission of the dataframe, a BA request (BAReq) on respective ones of the communicationlinks to the non-AP MLDs.

In some implementations, a different BAReq is transmitted for each ofthe non-AP MLDs, and wherein a BAReq for each of the non-AP MLDs is onlytransmitted on a single communication link. In some implementations, adifferent BAReq is transmitted for each of the non-AP MLDs, and whereina BAReq for each of the non-AP MLDs is transmitted on a plurality of thecommunication links. In some implementations, the process 1300 includesreceiving, from a non-AP MLD, a BA on a link on which a correspondingBAReq was transmitted to the non-AP MLD.

FIG. 14 depicts a flow diagram showing an example process 1400 for groupaddressed frame delivery over multi-link systems. The process 1400includes identifying (1402), by an access point (AP) in a wirelessnetwork, that a groupcast with retry (GCR) BlockAckReq is to betransmitted to one or more non-AP multilink devices (MLDs). The process1400 includes identifying (1404), by the AP in the wireless network, atraffic identifier (TID) related to frames subject to a GCR-BAagreement. The process 1400 includes generating (1406), by the AP in thewireless network, a frame that includes the GCR BlockAckReq and aTID_Info portion based on the TID. The process 1400 includestransmitting (1408), by the AP in the wireless network, the generatedframe. In some implementations, the generated frame is to requestTID-specific block acknowledgement (BA) from the non-AP MLDs.

FIG. 15 depicts a flow diagram showing an example process 1500 for groupaddressed frame delivery over multi-link systems. The process 1500includes identifying (1502), by an access point (AP) multilink device(MLD) in a wireless network, a data frame that is to be transmitted to aplurality of non-AP MLDs subject to a groupcast with retry (GCR) blockacknowledgement (BA) agreement. The process 1500 includes identifying(1504), by the AP MLD, respective communication links by which the APMLD is communicatively coupled with the non-AP MLDs. The process 1500includes transmitting (1506), by the AP MLD, the data frame on each ofthe respective communication links. The process 1500 includestransmitting (1508), by the AP MLD based on the transmission of the dataframe, a BA request (BAReq) on respective ones of the communicationlinks to the non-AP MLDs. In some implementations, the first frame andthe second frame are related to block acknowledgement (BA).

In some implementations, the process 1500 includes transmitting, to thenon-AP MLD, a group cast frame (GCF) wherein a transmit address (TA)field of the GCF is equivalent to the MLD_address of an AP MLD. In someimplementations, the process 1500 includes transmitting, to the non-APMLD, the first frame and the second frame based on a groupcast packetnumber (PN_gc) assigned by a common PN space used by the transmission ofgroup addressed frames over both the first communications link and thesecond communications link. In some implementations, the process 1500includes transmitting the first frame and the second frame based on ashared sequence number space (SNS) that is shared between the firstcommunications link and the second communications link.

FIG. 16 depicts a flow diagram showing an example process 1600 for groupaddressed frame delivery over multi-link systems. The process 1600includes identifying (1602), by a non-access point (AP) multilink device(MLD) in a wireless network, a first frame received on a first link anda second frame received on a second link. The process 1600 includesprocessing (1604), by a Group Frames and Reorder buffer of the non-APMLD, the first frame and the second frame to identify: (a) whether thefirst frame and second frame are duplicates of one another; and (b)whether the first frame and second frame have a sequence number (SN)that is in accordance with a pre-identified order. The process 1600includes outputting (1606), by the Group Frames and Reorder buffer ofthe non-AP MLD, the first frame and the second frame to a PN check anddecryption block if the first frame and second frame are not duplicatesof one another and have a SN that are in accordance with thepre-identified order.

In some implementations, the Group Frames and Reorder buffer identifiesthat the first frame and second frame have a SN that are in accordancewith the pre-identified order if there is no missing frame with asmaller SN than the first frame or second frame. In someimplementations, the non-AP MLD can receive group frames from one link(to save power) or from multiple links (to improve reliability). In someimplementations, if STA receives group frames from a single AP andchanges the AP from which it receives group frames, then the STA may useSN of the group frame to decide whether it has received all frames. Insome implementations, the group frames are not transmitted exactly inthe SN frame order. In some implementations, the Group Frames andReorder buffer identifies that the first frame and second frame have aSN that are in accordance with the pre-identified order if the non-APMLD has received a frame with higher SN that the first frame or secondframe on all links from which it receives the first frame and the secondframe. In some implementations, the process 1600 includes outputting, bythe Group Frames and Reorder buffer of the non-AP MLD, the first frameand the second frame if the non-AP MLD is unable to store a receivedthird frame in the Group Frames and Reorder buffer.

In the foregoing detailed description, reference is made to theaccompanying drawings which form a part hereof, wherein like numeralsdesignate like parts throughout, and in which is shown by way ofillustration embodiments in which the subject matter of the presentdisclosure may be practiced. It is to be understood that otherembodiments may be utilized and structural or logical changes may bemade without departing from the scope of the present disclosure.Therefore, the following detailed description is not to be taken in alimiting sense.

For the purposes of the present disclosure, the phrase “A or B” means(A), (B), or (A and B). For the purposes of the present disclosure, thephrase “A, B, or C” means (A), (B), (C), (A and B), (A and C), (B andC), or (A, B and C).

The description uses the phrases “in an embodiment,” or “inembodiments,” which may each refer to one or more of the same ordifferent embodiments. Furthermore, the terms “comprising,” “including,”“having,” and the like, as used with respect to embodiments of thepresent disclosure, are synonymous.

The term “coupled with,” along with its derivatives, may be used herein.“Coupled” may mean one or more of the following. “Coupled” may mean thattwo or more elements are in direct physical or electrical contact.However, “coupled” may also mean that two or more elements indirectlycontact each other, but yet still cooperate or interact with each other,and may mean that one or more other elements are coupled or connectedbetween the elements that are said to be coupled with each other. Theterm “directly coupled” may mean that two or elements are in directcontact.

Various operations may be described as multiple discrete operations inturn, in a manner that is most helpful in understanding the claimedsubject matter. However, the order of description should not beconstrued as to imply that these operations are necessarily orderdependent.

Embodiments herein are described with respect to various Figures. Unlessexplicitly stated, the dimensions of the Figures are intended to besimplified illustrative examples, rather than depictions of relativedimensions. For example, various lengths/widths/heights of elements inthe Figures may not be drawn to scale unless indicated otherwise.

EXAMPLES OF VARIOUS EMBODIMENTS

Example 1 includes a computer-implemented method comprising:identifying, by an access point (AP) multilink device (MLD) in awireless network, a first sequence number space (SNS) that is to be usedby the AP MLD to transmit data to a non-AP MLD over a firstcommunications link and a second communications link, wherein frameswith identical data that are transmitted over the first and secondcommunications links will have an identical first SN based on the firstSNS; identifying, by the MLD in the wireless network, the first SN basedon the first SNS; and transmitting, by the AP MLD in the wirelessnetwork, a frame that includes the data to the non-AP MLD based on thefirst SN.

Example 2 includes the computer-implemented method of example 1, or someother example herein, wherein the first frame is a frame related togroupcast data (G-Data) for quality of service (QoS), groupcast withretry (GCR) data, G-Data not requiring QoS, groupcast management datagenerated at the multilink (ML) level, Groupcast management datagenerated by the first AP, unicast management data generated at the MLlevel, and possibly unicast management data generated by the AP and isintended for the non-AP MLD.

Example 3 includes the computer-implemented method of example 1, or someother example herein, wherein the SNS is independent of a trafficidentifier value (TID) of the first frame for GCR-BA operation.

Example 4 includes the computer implemented method of example 1, or someother example herein, further comprising: identifying, by the MLD in thewireless network, a second SNS that is to be used by the MLD to transmitgroupcast with retry block acknowledgment (GCR-BA) data over the firstcommunications link and the second communications link, whereinidentical frames on the first and second communications links thatinclude identical GCR-BA data will have an identical second SN based onthe second SNS; identifying, by the MLD in the wireless network, thesecond SN based on the second SNS; and transmitting, by the AP MLD inthe wireless network, a frame that includes the GCR-BA data to thenon-AP MLD based on the second SN.

Example 5 includes the computer implemented method of example 4, or someother example herein, the identification of the second SNS is based on avalue of “address 1” of the frame that includes the GCR data.

Example 6 includes the computer implemented method of example 4, or someother example herein, wherein the second SNS is indexed by a trafficidentifier (TID) value of the frame that includes the GCR data.

Example 7 includes the computer-implemented method of example 1, or someother example herein, further comprising: identifying, by the MLD in thewireless network, a third SNS that is to be used by the MLD to transmitunicast management data over the first and second communications links,wherein identical frames on the first and second communications linksthat include identical unicast management data will have an identicalthird SN based on the third SNS, where the identification of the thirdSNS is based on a value of “address 1” and frame type of the frame;identifying, by the MLD in the wireless network, the third SN based onthe third SNS; and transmitting, by the AP MLD in the wireless network,a frame that includes the unicast management data to the non-AP MLDbased on the third SN.

Example 8 includes a computer-implemented method comprising:identifying, by an access point (AP) multilink device (MLD) in awireless network, a data frame that is to be transmitted to a pluralityof non-AP MLDs subject to a groupcast with retry (GCR) blockacknowledgement (BA) agreement; identifying, by the AP MLD, respectivecommunication links by which the AP MLD is communicatively coupled withthe non-AP MLDs; transmitting, by the AP MLD, the data frame on each ofthe respective communication links; and transmitting, by the AP MLDbased on the transmission of the data frame, a BA request (BAReq) onrespective ones of the communication links to the non-AP MLDs.

Example 9 includes the computer-implemented method of example 8, or someother example herein, wherein a different BAReq is transmitted for eachof the non-AP MLDs, and wherein a BAReq for each of the non-AP MLDs isonly transmitted on a single communication link.

Example 10 includes the computer-implemented method of example 8, orsome other example herein, wherein a different BAReq is transmitted foreach of the non-AP MLDs, and wherein a BAReq for each of the non-AP MLDsis transmitted on a plurality of the communication links.

Example 11 includes the computer-implemented method of example 8, orsome other example herein, wherein the method further comprisingreceiving, from a non-AP MLD, a BA on a link on which a correspondingBAReq was transmitted to the non-AP MLD

Example 12 includes a computer-implemented method comprising:identifying, by an access point (AP) in a wireless network, that agroupcast with retry (GCR) BlockAckReq is to be transmitted to one ormore non-AP multilink devices (MLDs); identify, by the AP in thewireless network, a traffic identifier (TID) related to frames subjectto a GCR-BA agreement; generate, by the AP in the wireless network, aframe that includes the GCR BlockAckReq and a TID_Info portion based onthe TID; and transmit, by the AP in the wireless network, the generatedframe.

Example 13 includes the computer-implemented method of example 12, orsome other example herein, wherein the generated frame is to requestTID-specific block acknowledgement (BA) from the non-AP MLDs.

Example 14 includes a computer-implemented method comprising:identifying, by an access point (AP) multilink device (MLD) in awireless network, a first communications link and a secondcommunications link by which the AP MLD is communicatively coupled witha non-AP MLD; identifying, by the AP MLD, a groupwise transient key(GTK); and transmitting, to the non-AP MLD, a first frame on the firstcommunications link based on the GTK, and a second frame on the secondcommunications link based on the same GTK.

Example 15 includes the computer-implemented method of example 14, orsome other example herein, wherein the first frame and the second frameare related to block acknowledgement (BA).

Example 16 includes the computer-implemented method of example 14, orsome other example herein, wherein the method further comprisestransmitting, to the non-AP MLD, a group cast frame (GCF) wherein atransmit address (TA) field of the GCF is equivalent to the MLD_addressof an AP MLD.

Example 17 includes the computer-implemented method of example 14, orsome other example herein, wherein the method further comprisestransmitting, to the non-AP MLD, the first frame and the second framebased on a groupcast packet number (PN_gc) assigned by a common PN spaceused by the transmission of group addressed frames over both the firstcommunications link and the second communications link.

Example 18 includes the computer-implemented method of example 14, orsome other example herein, wherein the method further comprisestransmitting the first frame and the second frame based on a sharedsequence number space (SNS) that is shared between the firstcommunications link and the second communications link.

Example 19 includes a computer-implemented method comprising:identifying, by a non-access point (AP) multilink device (MLD) in awireless network, a first frame received on a first link and a secondframe received on a second link; processing, by a group frames andreorder buffer of the non-AP MLD, the first frame and the second frameto identify: (a) whether the first frame and second frame are duplicatesof one another; and (b) whether the first frame and second frame have asequence number (SN) that is in accordance with a pre-identified order;and outputting, by the group frames and reorder buffer of the non-APMLD, the first frame and the second frame to a PN check and decryptionblock if the first frame and second frame are not duplicates of oneanother and have a SN that are in accordance with the pre-identifiedorder.

Example 20 includes the computer-implemented method of example 19, orsome other example herein, wherein the group frames and Reorder bufferidentifies that the first frame and second frame have a SN that are inaccordance with the pre-identified order if there is no missing framewith a smaller SN than the first frame or second frame.

Example 21 includes the computer-implemented method of example 19, orsome other example herein, wherein the non-AP MLD can receive groupframes from one link (to save power) or from multiple links (to improvereliability).

Example 22 includes the computer-implemented method of example 19, orsome other example herein, wherein if STA receives group frames from asingle AP and changes the AP from which it receives group frames, thenthe STA may use SN of the group frame to decide whether it has receivedall frames.

Example 23 includes the computer-implemented method of example 22, orsome other example herein, wherein the group frames are not transmittedexactly in the SN frame order.

Example 24 includes the computer-implemented method of example 19, orsome other example herein, wherein the group frames and Reorder bufferidentifies that the first frame and second frame have a SN that are inaccordance with the pre-identified order if the non-AP MLD has receiveda frame with higher SN that the first frame or second frame on all linksfrom which it receives the first frame and the second frame.

Example 25 includes the computer-implemented method of example 19, orsome other example herein, wherein the method further comprisesoutputting, by the group frames and Reorder buffer of the non-AP MLD,the first frame and the second frame if the non-AP MLD is unable tostore a received third frame in the group frames and reorder buffer.

Example 26 includes a computer-implemented method, wherein separateoperation on AP MLD group casts group frames to legacy receivable formatin some AP.

Example 27 includes the computer-implemented method of example 26, orsome other example herein, wherein the AP MLD decides on which APgroupcasts the group management frames in legacy STA-receivable format.

Example 28 includes the computer-implemented method of example 26, orsome other example herein, wherein the non-AP MLD signals in UL framethe AP(s) in AP that DL group cast the UL frame in legacy receivableformat.

Example 29 includes the computer-implemented method of example 26, orsome other example herein, wherein the AP parses the UL data frame anduses address information or payload to decide the AP that group caststhe frame in legacy STA receivable format.

Example 30 includes the computer-implemented method of example 26, orsome other example herein, wherein the AP sends UL data frames fromlegacy STA that it should group cast in legacy receivable format only inthe AP that received the UL frame and in non-AP MLD receivable format inother Aps in AP MLD.

Example 31 includes a computer-implemented method comprisingtransmitting, by an access point (AP) multi-link device (MLD) groupaddressed management frames and group addressed data frames so thatlegacy stations (STAs) can receive the frames only from a single AP orfrom subset of APs, but non-AP MLDs can receive the group addressedframe in all links.

Example 32 includes the computer-implemented method of example 31, orsome other example herein, wherein the group addressed frame istransmitted in a physical layer protocol data unit (PPDU) format that isreceivable only by the non-AP MLDs.

Example 33 includes the computer-implemented method of example 31, orsome other example herein, wherein the group addressed frames aretransmitted in a new frame type that is understood only by the non-APMLDs, and the legacy STAs are not able to understand the frame content.

Example 34 includes the computer-implemented method of examples 32 or 33above, or some other example herein, wherein the new PPDU type and newframe contain information that identifies the AP(s) in AP MLD that isgroup casting the legacy receivable frame.

Example 35 includes the computer-implemented method of example 31, orsome other example herein, wherein the AP transmits link-specificindividually addressed management frames to a non-AP MLD.

Example 36 includes the computer-implemented method of example 31, orsome other example herein, wherein the AP MLD unicasts a copy of all orselected group addressed frames to a non-AP MLD.

Example 37 includes the computer-implemented method of example 31, orsome other example herein, wherein the non-AP MLD transmits an uplink(UL) unicast frame that requests AP MLD to DL group cast the UL frame toassociated STAs in AP MLD.

Example 38 includes the computer-implemented method of example 37, orsome other example herein, wherein the non-AP MLD signals in the ULunicast frame that signals to AP the set of APs in which the frameshould be group casted in legacy receivable format.

Example 39 includes the computer-implemented method of example 37, orsome other example herein, wherein the AP MLD is to parse the UL unicastframes that contain a frame that will be DL group casted by the AP.

Various embodiments may include any suitable combination of theabove-described embodiments including alternative (or) embodiments ofembodiments that are described in conjunctive form (and) above (e.g.,the “and” may be “and/or”). Furthermore, some embodiments may includeone or more articles of manufacture (e.g., non-transitorycomputer-readable media) having instructions, stored thereon, that whenexecuted result in actions of any of the above-described embodiments.Moreover, some embodiments may include apparatuses or systems having anysuitable means for carrying out the various operations of theabove-described embodiments.

The above description of illustrated embodiments, including what isdescribed in the Abstract, is not intended to be exhaustive or limitingas to the precise forms disclosed. While specific implementations of,and examples for, various embodiments or concepts are described hereinfor illustrative purposes, various equivalent modifications may bepossible, as those skilled in the relevant art will recognize. Thesemodifications may be made in light of the above detailed description,the Abstract, the Figures, or the claims.

What is claimed is:
 1. A computer-implemented method comprising:identifying, by an access point (AP) multilink device (MLD) in awireless network, a first sequence number space (SNS) that is to be usedby the AP MLD to transmit data to a non-AP MLD over a firstcommunications link and a second communications link, wherein frameswith identical data that are transmitted over the first and secondcommunications links will have an identical first SN based on the firstSNS; identifying, by the AP MLD in the wireless network, the first SNbased on the first SNS; and transmitting, by the AP MLD in the wirelessnetwork, a frame that includes the data to the non-AP MLD based on thefirst SN; identifying, by the AP MLD in the wireless network, a secondSNS that is to be used by the AP MLD to transmit groupcast with retryblock acknowledgment (GCR-BA) data over the first communications linkand the second communications link, wherein identical frames unicast onthe first and second communications links that include identical GCR-BAdata have an identical second SN based on the second SNS; identifying,by the AP MLD in the wireless network, the second SN based on the secondSNS; and transmitting, by the AP MLD in the wireless network, a framethat includes the GCR-BA data to the non-AP MLD based on the second SN.2. The computer-implemented method of claim 1, wherein the frame isrelated to one or more of groupcast data (G-Data) for quality of service(QoS), groupcast with retry (GCR) data, G-Data not requiring QoS,groupcast management data generated at the multilink (ML) level,Groupcast management data generated by the first AP, unicast managementdata generated at a ML level, and possibly unicast management datagenerated by the AP and is intended for the non-AP MLD.
 3. Thecomputer-implemented method of claim 1, wherein the SNS is independentof a traffic identifier value (TID) of the frame for GCR-BA operation.4. The computer implemented method of claim 1, the identification of thesecond SNS is based on a value of “address 1” of the frame that includesGCR data.
 5. The computer implemented method of claim 1, wherein thesecond SNS is indexed by a traffic identifier (TID) value of the framethat includes GCR data.
 6. The computer-implemented method of claim 1,further comprising: identifying, by the AP MLD in the wireless network,a third SNS that is to be used by the AP MLD to transmit unicastmanagement data over the first and second communications links, whereinidentical frames on the first and second communications links thatinclude identical unicast management data will have an identical thirdSN based on the third SNS, where the identification of the third SNS isbased on a value of “address 1” and frame type of the frame;identifying, by the AP MLD in the wireless network, the third SN basedon the third SNS; and transmitting, by the AP MLD in the wirelessnetwork, a frame that includes the unicast management data to the non-APMLD based on the third SN.
 7. A computer-implemented method comprising:identifying, by an access point (AP) multilink device (MLD) in awireless network, a data frame that is to be transmitted to a pluralityof non-AP MLDs subject to a groupcast with retry (GCR) blockacknowledgement (BA) agreement; identifying, by the AP MLD, respectivecommunication links by which the AP MLD is communicatively coupled withthe non-AP MLDs; transmitting, by the AP MLD, the data frame on each ofthe respective communication links; and transmitting, by the AP MLDbased on transmission of the data frame, a BA request (BAReq) onrespective ones of the communication links to the non-AP MLD; andwherein a different BAReq is transmitted for each of the non-AP MLDs. 8.The computer-implemented method of claim 7, wherein a BAReq for each ofthe non-AP MLDs is only transmitted on a single communication link. 9.The computer-implemented method of claim 7, wherein a BAReq for each ofthe non-AP MLDs is transmitted on a plurality of the communicationlinks.
 10. The computer-implemented method of claim 7, wherein themethod further comprising receiving, from a non-AP MLD, a BA on a linkon which a corresponding BAReq was transmitted to the non-AP MLD.
 11. Acomputer-implemented method comprising: identifying, by a non-accesspoint (AP) multilink device (MLD) in a wireless network, a first framereceived on a first link and a second frame received on a second link;processing, by a group frames and reorder buffer of the non-AP MLD, thefirst frame and the second frame to identify: (a) whether the firstframe and second frame are duplicates of one another; and (b) whetherthe first frame and second frame have a sequence number (SN) that is inaccordance with a pre-identified order; and outputting, by the groupframes and reorder buffer of the non-AP MLD, the first frame and thesecond frame to a PN check and decryption block when the first frame andsecond frame are not duplicates of one another and have respective SNsthat are in accordance with the pre-identified order.
 12. Thecomputer-implemented method of claim 11, wherein the group frames andreorder buffer identifies that the first frame and second frame have aSN that are in accordance with the pre-identified order when there is nomissing frame with a smaller SN than the first frame or second frame.13. The computer-implemented method of claim 11, wherein the non-AP MLDreceives group frames from one link to save power or from multiple linksto improve reliability.
 14. The computer-implemented method of claim 11,wherein when a station (STA) receives group frames from a single AP andthe STA changes the AP from which the STA receives group frames, the STAdetermines, based on a SN of the group frame, whether the STA hasreceived all of the group frames.
 15. The computer-implemented method ofclaim 14, wherein the group frames are not transmitted exactly in aframe order designated by the SN.
 16. The computer-implemented method ofclaim 11, wherein the group frames and reorder buffer identifies thatthe first frame and second frame have respective SNs that are each inaccordance with the pre-identified order when the non-AP MLD hasreceived a frame with higher SN that the first frame or second frame onall links from which it receives the first frame and the second frame.17. The computer-implemented method of claim 11, wherein the methodfurther comprises outputting, by the group frames and reorder buffer ofthe non-AP MLD, the first frame and the second frame when the non-AP MLDis unable to store a received third frame in the group frames andreorder buffer.
 18. The computer-implemented method of claim 11, whereinthe first frame is related to one or more of groupcast data (G-Data) forquality of service (QoS), groupcast with retry (GCR) data, G-Data notrequiring QoS, groupcast management data generated at the multilink (ML)level, groupcast management data generated by the first AP, unicastmanagement data generated at a ML level, and unicast management datagenerated by the AP and is intended for the non-AP MLD.
 19. The computerimplemented method of claim 11, further comprising: identifying, by theAP MLD in the wireless network, a SNS that is to be used by the AP MLDto transmit groupcast with retry block acknowledgment (GCR-BA) data overthe first link and the second link, wherein identical frames on thefirst and second links that include identical GCR-BA data will have anidentical second SN based on the SNS; identifying, by the AP MLD in thewireless network, the second SN based on the second SNS; andtransmitting, by the AP MLD in the wireless network, a frame thatincludes the GCR-BA data to the non-AP MLD based on the second SN.